function creds = loadplotlycredentials()
    userhome = getuserdir();

    plotly_credentials_file = fullfile(userhome, '.plotly', '.credentials');

    % check if credentials exist
    if ~exist(plotly_credentials_file, 'file')
        error('Plotly:CredentialsNotFound', ['It looks like you ' ...
                'haven''t set up your plotly account credentials ' ...
                'yet.\nTo get started, save your plotly username and ' ...
                'API key by calling:\n>>> saveplotlycredentials(' ...
                'username, api_key)\n\nFor more help, see ' ...
                'https://plot.ly/MATLAB or contact chris@plot.ly.']);
    end

    fileIDCred = fopen(plotly_credentials_file, 'r');

    if (fileIDCred == -1)
        error('plotly:loadcredentials', ['There was an error reading ' ...
                'your credentials file at ' plotly_credentials_file ...
                '. Contact chris@plot.ly for support.']);
    end

    creds_string_array = fread(fileIDCred, '*char');
    creds_string = sprintf('%s',creds_string_array);
    creds = jsondecode(creds_string);
end
